The present invention relates to a dispenser for dispensing a fluid substance, the dispenser comprising a container having a neck, and a dispenser member, such as a pump or a valve, mounted on the neck so as to extract the fluid. The invention relates more particularly to a fixing ring for fixing said dispenser member to a neck provided with an outwardly-projecting peripheral thick portion which co-operates with the remainder of the neck to form a bottom shoulder. That type of container with such a neck is in widespread use for pumps or valves that are snap-fastened onto the neck by using the bottom shoulder as a retaining or abutment surface.
Document FR-0 704 251 discloses a fixing ring provided with snap-fastening catches at the ends of which snap-fastening lugs designed to be received under the shoulder on the neck are formed. A band then covers the ring to prevent the lugs from being released from under the shoulder. With that type of fixing device, it is possible to remove the ring from the neck so long as the band is not mounted. The snap-fastening catches are flexible, which makes it possible for the lugs to pass over the thick portion to reach the snap-fastening position under the shoulder. Therefore, on mounting the ring on such a neck, the catches must bend outwards, which increases the working diameter of the ring as it passes over the thick portion of the neck. In addition, the ring is permanently fixed only once the band has been mounted: the fixing thus requires two parts.
Document U.S. Pat. No. 4,773,553 discloses another fixing device in which the fixing ring is made of a plastically-deformable material and is provided with catches having heads initially projecting outwards. It is thus possible to mount the ring on the neck without deforming the catches outwards. Final fixing is achieved by engaging a band by force over the ring so that the outwardly-projecting catches are brought back inwards under the shoulder on the neck by the material being deformed plastically. In which case, two parts are also necessary to perform the fixing, and, in addition, some force must be exerted on the band to cause the heads to deform inwards.
Document U.S. Pat. No. 5,299,703 describes a pump-fixing system in which a ring is provided with catches terminated by heads formed inwardly-projected bulges. Prior to being mounted the bulging heads are bent outwards to enable the neck to pass between them. Once in position on the neck of the container, the heads are deformed inwards by means of a band. That system is analogous to the system of Document U.S. Pat. No. 4,773,553, except that the ring is made of metal, and that the heads are bent inwards rather than being caused to deform plastically. Since the ring is made of metal, that system can be likened to crimping because the metal is deformed so as to reduce the inside diameter of the ring. It is also necessary to use a tool to fix the ring to the neck of the container.
An object of the present invention is to remedy the drawbacks of the above-mentioned prior art by providing a fixing device whose fixing ring achieves permanent fixing without requiring a separate band, and in which mounting the ring involves no deformation of the ring relative to its normal rest dimensions.
To this end, the present invention provides a fixing device for a dispenser for dispensing a fluid substance, the dispenser being suitable for being fitted to a container provided with a neck, and comprising a dispenser member mounted on the neck of the container, said neck forming an outwardly-extending peripheral thick portion co-operating with the remainder of the neck to form a bottom shoulder, said fixing device comprising a fixing ring for fixing the dispenser member to the neck, the fixing ring being provided with a peripheral skirt which extends to below said shoulder, said skirt being provided with flaps whose free ends point inwards and upwards and come into abutment contact against the shoulder, thereby snap-fastening the fixing ring to the neck of the container. On passing over the thick portion, the flaps are situated within the skirt without projecting outwards beyond it, and they can then be bent or can then take up their snap-fastening angular position under the shoulder. Advantageously, the flaps are pre-stressed to point inwards during manufacture of the fixing ring. In which case, the flaps return automatically to their original pre-stressed angular positions in which they point inwards as soon as they go past the thick portion. In a variant, the flaps are urged inwards once the ring is in position on the neck. In which case, a subsequent operation is necessary in order to bend the flaps under the shoulder. In both cases, the fixing is achieved by the ring on its own, without requiring an additional band. The flap ends that are in abutment against the shoulder guarantee permanent fixing on their own.
Preferably, the thickness of the wall of each of the flaps is equal to or less than the thickness of the wall of the skirt so that they do not project from the skirt as the flaps pass over the peripheral thick portion of the neck. It is thus possible to pre-mount the fixing ring inside a decorative trim band, and then to mount the resulting assembly on the container neck. Whereas, in the prior art, the snap-fastening catches must be deformed outwards to pass over the thick portion, in the present invention, the flaps are never deformed outwards, which makes it possible to pre-mount a band that is purely decorative since it is not necessary for fixing the ring to the neck.
The present invention also provides a dispenser including such a fixing device for fixing the dispenser member to the neck of the container.
The invention is described more fully below with reference to the sole FIGURE which, by way of non-limiting example, shows a cross-section through an embodiment of a dispenser of the invention.